1. Field of Invention
The present invention relates to a projector projecting an image by using spatial light modulation devices, such as liquid crystal panels.
2. Description of Related Art
Among related art rear projection projectors, a shallow rear projector is prevailing, in which image light emitted from a projection optical system disposed behind and at the lower part of a screen is eventually reflected toward the forward direction, while being reflected at at least one plane mirror to secure a light path, so as to be projected onto the screen See Japanese Unexamined Patent Application Publication No. 5-66482.
A projection display apparatus in which a diagonal projection having a large magnification is possible by forming its projection optical system with a plurality of concave and convex mirrors having different optical axes from each other has been proposed. See Japanese Unexamined Patent Application Publication No. 2001-255462. The projection display apparatus has a thin structure by achieving a high magnification and a diagonal projection.